The high reactivity of the azide group has prompted studies of the preparation of polymeric azides, since this moiety can be subsequently be converted with ease to several other types of substituent groups. The materials described herein are of special interest because of their ease of preparation from low-cost cellulose. The approach has been used to prepare other organic azides, but has not been employed to introduce the azide group into nitrocellulose for an improved propellant composition.